A general word of advice on sightseeing in New York:

Tourists often spend their entire vacation in New York standing in line (or as New Yorkers say, "standing on line"). This is often unnecessary; there are usually alternatives. For example, one can choose to avoid the Empire State Building during the day (it is open, and empty, late, until midnight or 2AM on weekends during summer), skip the Statue of Liberty in favor of the Staten Island Ferry, and stay away from the Guggenheim on Monday. Also, there is no reason to stand in line for a Broadway show if you already have a ticket with an assigned seat. If you prefer, get a drink nearby and come back closer to curtain time, when you can walk right in. The lines for bus tours can be absurd because tourists all seem to have the exact same itinerary - which is get on a bus in the morning in Times Square, get off for the Statue of Liberty, and finish on the East Side in the afternoon. Why not go downtown in the morning, and save Midtown for the afternoon, You will thank yourself for avoiding the crowds. Also, understand that buses are the slowest way to go crosstown in Midtown Manhattan during peak hours, and taxis are not much better. You are often better off on foot.

Entertainment:
Theater and Performing Arts:
New York has a wide variety of musical and dance companies, including several that are among the world's most renowned. There are also numerous small companies putting on more idiosyncratic shows every night of the week. The following are just a few of New York's most high-profile music and dance options.

Brooklyn Academy of Music: 30 Lafayette Avenue, Brooklyn. Home to the impressive Brooklyn Philharmonic, BAM is one of the best places in the country to attend cutting-edge new musical and dance performances. The Next Wave Festival every autumn is a much-anticipated event of the New York performance scene.

Carnegie Hall: 881 Seventh Avenue. The premier venue for classical music in the United States, Carnegie Hall is famous around the world for its dazzling performances. Playing at Carnegie Hall is, for many classical musicians, the epitome of success. Carnegie Hall houses three different auditoriums, with the Isaac Stern auditorium being the largest venue.

Chamber Music Society of Lincoln Center: at Alice Tully Hall in Lincoln Center, 155 West 65th Street (at Broadway). The Chamber Music Society is the most prestigious chamber music ensemble in the United States, playing in the acoustically impeccable Alice Tully Hall.

Metropolitan Opera: at Metropolitan Opera House in Lincoln Center, 155 West 65th Street (at Broadway). The Met (as it is known) is one of the greatest opera companies in the world. The company performs six days a week (Monday-Saturday) during the season (September-April), and always lands the greatest singers from around the globe. Expect to pay a small fortune for the most expensive seats, but upper-tier seats can cost as little as $25.

New York City Opera: at New York State Theater in Lincoln Center, 155 West 65th Street (at Broadway). (Closed for renovations until Fall 2009.) The slightly more accessible and energetic younger sister of the Met, the NYCO is a world-class company that puts on a dynamic range of performances. Plus, tickets can go for as little as $16.

New York City Ballet: at New York State Theater in Lincoln Center, 155 West 65th Street (at Broadway). Founded by George Balanchine, the New York City Ballet is among the world's best dance companies. Their performances of the The Nutcracker, during the holiday season, are enormously popular.

New York Philharmonic: at Avery Fisher Hall in Lincoln Center, 155 West 65th Street (at Broadway). One of the premier orchestras in the United States, playing a wide variety of concerts (more than 100) every year to sold out crowds, the Philharmonic is well known for its standard-setting performances of the classical canon. The season runs from September to June, and in the summer they play free concerts in parks around the city.

Radio City Music Hall: 1260 Avenue of the Americas, (212) 632-3975. See the Rockettes, another show or just tour the famous Art Deco masterpiece.

Parades:
New York City hosts many parades, street festivals and outdoor pageants. The following are the most famous:

New York's Village Halloween Parade: Each Halloween (October 31) at 7PM. This parade and street pageant attracts 2 million spectators and 50,000 costumed participants along Sixth Avenue between Spring Street and 21st Street. Anyone in a costume is welcome to march; those wishing to should show up between 6PM-9PM at Spring Street and 6th Avenue.

Macy's Thanksgiving Day Parade: The morning of each Thanksgiving on Central Park West, this parade attracts many spectators and is broadcast on nationwide television.

St. Patrick's Day Parade:
The largest St. Paddy's parade in the world! Route is up 5th
Ave from 44th Street to 86th Street and lasts from 11AM to about 2:30. Celebrations in pubs citywide happen the rest of the day and night until the green beer runs out.

Labor Day (aka West Indian Day Parade or New York Carribean Carnival): The Labor Day Carnival, or West Indian Carnival, is an annual celebration held in Crown Heights, Brooklyn, New York. Its main event is the West Indian-American Day Parade, which attracts between one and three million spectators, thus taking in more foot traffic in one day than the entirety of Toronto's Caribana festival. The spectators watch the parade on its route along Eastern Parkway. The large parade is held on American Labor Day, the first Monday in September.